SOC. You are putting up a brave fight, Theaetetus. But is not the all precisely that of which nothing is wanting?

THEAET. Necessarily.

SOC. And is not just this same thing, from which nothing whatsoever is lacking, a whole? For that from which anything is lacking is neither a whole nor all, which have become identical simultaneously and for the same reason.

THEAET. I think now that there is no difference between all and whole.

SOC. We were saying, were we not, that if there are parts of anything, the whole and all of it will be all the parts?

THEAET. Certainly.

SOC. Once more, then, as I was trying to say just now, if the syllable is not the letters, does it not follow necessarily that it contains the letters, not as parts of it, or else that being the same as the letters, it is equally knowable with them?

THEAET. It does.

SOC. And it was in order to avoid this that we assumed that it was different from them?

THEAET. Yes.

SOC. Well then, if the letters are not parts of the syllable, can you mention any other things which are parts of it, but are not the letters The reader is reminded that words στοιχεῖον and συλλαβή have the meanings element and combination as well as letter and syllable. of it?

THEAET. Certainly not. For if I grant that there are parts of the syllable, it would be ridiculous to give up the letters and look for other things as parts.

SOC. Without question, then, Theaetetus, the syllable would be, according to our present view, some indivisible concept.

THEAET. I agree.

SOC. Do you remember, then, my friend, that we admitted a little while ago, on what we considered good grounds, that there can be no rational explanation of the primary elements of which other things are composed, because each of them, when taken by itself, is not composite, and we could not properly apply to such an element even the expression be or this, because these terms are different and alien, and for this reason it is irrational and unknowable?

THEAET. I remember.

SOC. And is not this the sole reason why it is single in form and indivisible? I can see no other.

THEAET. There is no other to be seen.

SOC. Then the syllable falls into the same class with the letter, if it has no parts and is a single form?

THEAET. Yes, unquestionably.

SOC. If, then, the syllable is a plurality of letters and is a whole of which the letters are parts, the syllables and the letters are equally knowable and expressible, if all the parts were found to be the same as the whole.

THEAET. Certainly.

SOC. But if one and indivisible, then syllable and likewise letter are equally irrational and unknowable; for the same cause will make them so.

THEAET. I cannot dispute it.

SOC. Then we must not accept the statement of any one who says that the syllable is knowable and expressible, but the letter is not.

THEAET. No, not if we are convinced by our argument.